An X-ray CT scanner includes X-ray tubes including a first X-ray tube and a second X-ray tube having fan angles different from each other, X-ray detectors including a first X-ray detector and a second X-ray detector which are respectively arranged to face the first X-ray tube and the second X-ray tube, collection data processing means for executing weighting processing to each of pieces of collection data including first collection data (Ds1) obtained by the first X-ray detector and second collection data (Dm) obtained by the second X-ray detector to generate image data combined to be smooth in a direction corresponding to a channel direction of detection elements provided in the X-ray detectors, and image generating section for performing processing including image reconstruction processing with respect to pieces of collection data (Dwsl, Dwm) weighted by the collection data processing section to generate image data (I).